Beispiel #1
0
    async def receive_handshake(self, reader: asyncio.StreamReader,
                                writer: asyncio.StreamWriter) -> None:
        # Use reader to read the auth_init msg until EOF
        msg = await reader.read(ENCRYPTED_AUTH_MSG_LEN)

        # Use HandshakeResponder.decode_authentication(auth_init_message) on auth init msg
        try:
            ephem_pubkey, initiator_nonce, initiator_pubkey = decode_authentication(
                msg, self.privkey)
        # Try to decode as EIP8
        except DecryptionError:
            msg_size = big_endian_to_int(msg[:2])
            remaining_bytes = msg_size - ENCRYPTED_AUTH_MSG_LEN + 2
            msg += await reader.read(remaining_bytes)
            ephem_pubkey, initiator_nonce, initiator_pubkey = decode_authentication(
                msg, self.privkey)

        # Get remote's address: IPv4 or IPv6
        ip, port, *_ = writer.get_extra_info("peername")
        remote_address = Address(ip, port)

        # Create `HandshakeResponder(remote: kademlia.Node, privkey: datatypes.PrivateKey)` instance
        initiator_remote = Node(initiator_pubkey, remote_address)
        responder = HandshakeResponder(initiator_remote, self.privkey)

        # Call `HandshakeResponder.create_auth_ack_message(nonce: bytes)` to create the reply
        responder_nonce = secrets.token_bytes(HASH_LEN)
        auth_ack_msg = responder.create_auth_ack_message(nonce=responder_nonce)
        auth_ack_ciphertext = responder.encrypt_auth_ack_message(auth_ack_msg)

        # Use the `writer` to send the reply to the remote
        writer.write(auth_ack_ciphertext)
        await writer.drain()

        # Call `HandshakeResponder.derive_shared_secrets()` and use return values to create `Peer`
        aes_secret, mac_secret, egress_mac, ingress_mac = responder.derive_secrets(
            initiator_nonce=initiator_nonce,
            responder_nonce=responder_nonce,
            remote_ephemeral_pubkey=ephem_pubkey,
            auth_init_ciphertext=msg,
            auth_ack_ciphertext=auth_ack_ciphertext)

        # Create and register peer in peer_pool
        eth_peer = ETHPeer(remote=initiator_remote,
                           privkey=self.privkey,
                           reader=reader,
                           writer=writer,
                           aes_secret=aes_secret,
                           mac_secret=mac_secret,
                           egress_mac=egress_mac,
                           ingress_mac=ingress_mac,
                           chaindb=self.chaindb,
                           network_id=self.network_id)
        self.peer_pool.add_peer(eth_peer)
Beispiel #2
0
    async def receive_connection(cls, reader: asyncio.StreamReader,
                                 writer: asyncio.StreamWriter,
                                 private_key: datatypes.PrivateKey,
                                 token: CancelToken) -> TransportAPI:
        try:
            msg = await token.cancellable_wait(
                reader.readexactly(ENCRYPTED_AUTH_MSG_LEN),
                timeout=REPLY_TIMEOUT,
            )
        except asyncio.IncompleteReadError as err:
            raise HandshakeFailure from err

        try:
            ephem_pubkey, initiator_nonce, initiator_pubkey = decode_authentication(
                msg,
                private_key,
            )
        except DecryptionError as non_eip8_err:
            # Try to decode as EIP8
            msg_size = big_endian_to_int(msg[:2])
            remaining_bytes = msg_size - ENCRYPTED_AUTH_MSG_LEN + 2

            try:
                msg += await token.cancellable_wait(
                    reader.readexactly(remaining_bytes),
                    timeout=REPLY_TIMEOUT,
                )
            except asyncio.IncompleteReadError as err:
                raise HandshakeFailure from err

            try:
                ephem_pubkey, initiator_nonce, initiator_pubkey = decode_authentication(
                    msg,
                    private_key,
                )
            except DecryptionError as eip8_err:
                raise HandshakeFailure(
                    f"Failed to decrypt both EIP8 handshake: {eip8_err}  and "
                    f"non-EIP8 handshake: {non_eip8_err}")
            else:
                got_eip8 = True
        else:
            got_eip8 = False

        peername = writer.get_extra_info("peername")
        if peername is None:
            socket = writer.get_extra_info("socket")
            sockname = writer.get_extra_info("sockname")
            raise HandshakeFailure(
                "Received incoming connection with no remote information:"
                f"socket={repr(socket)}  sockname={sockname}")

        ip, socket, *_ = peername
        remote_address = Address(ip, socket)

        cls.logger.debug("Receiving handshake from %s", remote_address)

        initiator_remote = Node(initiator_pubkey, remote_address)

        responder = HandshakeResponder(initiator_remote, private_key, got_eip8,
                                       token)

        responder_nonce = secrets.token_bytes(HASH_LEN)

        auth_ack_msg = responder.create_auth_ack_message(responder_nonce)
        auth_ack_ciphertext = responder.encrypt_auth_ack_message(auth_ack_msg)

        # Use the `writer` to send the reply to the remote
        writer.write(auth_ack_ciphertext)
        await token.cancellable_wait(writer.drain())

        # Call `HandshakeResponder.derive_shared_secrets()` and use return values to create `Peer`
        aes_secret, mac_secret, egress_mac, ingress_mac = responder.derive_secrets(
            initiator_nonce=initiator_nonce,
            responder_nonce=responder_nonce,
            remote_ephemeral_pubkey=ephem_pubkey,
            auth_init_ciphertext=msg,
            auth_ack_ciphertext=auth_ack_ciphertext)

        transport = cls(
            remote=initiator_remote,
            private_key=private_key,
            reader=reader,
            writer=writer,
            aes_secret=aes_secret,
            mac_secret=mac_secret,
            egress_mac=egress_mac,
            ingress_mac=ingress_mac,
        )
        return transport
Beispiel #3
0
    async def _receive_handshake(self, reader: asyncio.StreamReader,
                                 writer: asyncio.StreamWriter) -> None:
        msg = await self.wait(reader.read(ENCRYPTED_AUTH_MSG_LEN),
                              timeout=REPLY_TIMEOUT)

        ip, socket, *_ = writer.get_extra_info("peername")
        remote_address = Address(ip, socket)
        self.logger.debug("Receiving handshake from %s", remote_address)
        got_eip8 = False
        try:
            ephem_pubkey, initiator_nonce, initiator_pubkey = decode_authentication(
                msg, self.privkey)
        except DecryptionError:
            # Try to decode as EIP8
            got_eip8 = True
            msg_size = big_endian_to_int(msg[:2])
            remaining_bytes = msg_size - ENCRYPTED_AUTH_MSG_LEN + 2
            msg += await self.wait(reader.read(remaining_bytes),
                                   timeout=REPLY_TIMEOUT)
            try:
                ephem_pubkey, initiator_nonce, initiator_pubkey = decode_authentication(
                    msg, self.privkey)
            except DecryptionError as e:
                self.logger.debug("Failed to decrypt handshake: %s", e)
                return

        initiator_remote = Node(initiator_pubkey, remote_address)
        responder = HandshakeResponder(initiator_remote, self.privkey,
                                       got_eip8, self.cancel_token)

        responder_nonce = secrets.token_bytes(HASH_LEN)
        auth_ack_msg = responder.create_auth_ack_message(responder_nonce)
        auth_ack_ciphertext = responder.encrypt_auth_ack_message(auth_ack_msg)

        # Use the `writer` to send the reply to the remote
        writer.write(auth_ack_ciphertext)
        await self.wait(writer.drain())

        # Call `HandshakeResponder.derive_shared_secrets()` and use return values to create `Peer`
        aes_secret, mac_secret, egress_mac, ingress_mac = responder.derive_secrets(
            initiator_nonce=initiator_nonce,
            responder_nonce=responder_nonce,
            remote_ephemeral_pubkey=ephem_pubkey,
            auth_init_ciphertext=msg,
            auth_ack_ciphertext=auth_ack_ciphertext)

        # Create and register peer in peer_pool
        peer = self.peer_class(
            remote=initiator_remote,
            privkey=self.privkey,
            reader=reader,
            writer=writer,
            aes_secret=aes_secret,
            mac_secret=mac_secret,
            egress_mac=egress_mac,
            ingress_mac=ingress_mac,
            headerdb=self.headerdb,
            network_id=self.network_id,
            inbound=True,
        )

        if self.peer_pool.is_full:
            peer.disconnect(DisconnectReason.too_many_peers)
        else:
            # We use self.wait() here as a workaround for
            # https://github.com/ethereum/py-evm/issues/670.
            await self.wait(self.do_handshake(peer))
Beispiel #4
0
    async def _receive_handshake(
            self, reader: asyncio.StreamReader, writer: asyncio.StreamWriter) -> None:
        msg = await self.wait_first(
            reader.read(ENCRYPTED_AUTH_MSG_LEN),
            timeout=REPLY_TIMEOUT)

        ip, socket, *_ = writer.get_extra_info("peername")
        remote_address = Address(ip, socket)
        self.logger.debug("Receiving handshake from %s", remote_address)
        try:
            ephem_pubkey, initiator_nonce, initiator_pubkey = decode_authentication(
                msg, self.privkey)
        except DecryptionError:
            # Try to decode as EIP8
            msg_size = big_endian_to_int(msg[:2])
            remaining_bytes = msg_size - ENCRYPTED_AUTH_MSG_LEN + 2
            msg += await self.wait_first(
                reader.read(remaining_bytes),
                timeout=REPLY_TIMEOUT)
            try:
                ephem_pubkey, initiator_nonce, initiator_pubkey = decode_authentication(
                    msg, self.privkey)
            except DecryptionError as e:
                self.logger.debug("Failed to decrypt handshake: %s", e)
                return

        # Create `HandshakeResponder(remote: kademlia.Node, privkey: datatypes.PrivateKey)` instance
        initiator_remote = Node(initiator_pubkey, remote_address)
        responder = HandshakeResponder(initiator_remote, self.privkey, self.cancel_token)

        # Call `HandshakeResponder.create_auth_ack_message(nonce: bytes)` to create the reply
        responder_nonce = secrets.token_bytes(HASH_LEN)
        auth_ack_msg = responder.create_auth_ack_message(nonce=responder_nonce)
        auth_ack_ciphertext = responder.encrypt_auth_ack_message(auth_ack_msg)

        # Use the `writer` to send the reply to the remote
        writer.write(auth_ack_ciphertext)
        await writer.drain()

        # Call `HandshakeResponder.derive_shared_secrets()` and use return values to create `Peer`
        aes_secret, mac_secret, egress_mac, ingress_mac = responder.derive_secrets(
            initiator_nonce=initiator_nonce,
            responder_nonce=responder_nonce,
            remote_ephemeral_pubkey=ephem_pubkey,
            auth_init_ciphertext=msg,
            auth_ack_ciphertext=auth_ack_ciphertext
        )

        # Create and register peer in peer_pool
        peer = self.peer_class(
            remote=initiator_remote,
            privkey=self.privkey,
            reader=reader,
            writer=writer,
            aes_secret=aes_secret,
            mac_secret=mac_secret,
            egress_mac=egress_mac,
            ingress_mac=ingress_mac,
            headerdb=self.headerdb,
            network_id=self.network_id,
            inbound=True,
        )

        await self.do_handshake(peer)
Beispiel #5
0
    async def _receive_handshake(
            self, reader: asyncio.StreamReader, writer: asyncio.StreamWriter) -> None:
        msg = await self.wait(
            reader.read(ENCRYPTED_AUTH_MSG_LEN),
            timeout=REPLY_TIMEOUT)

        peername = writer.get_extra_info("peername")
        if peername is None:
            socket = writer.get_extra_info("socket")
            sockname = writer.get_extra_info("sockname")
            raise HandshakeFailure(
                "Received incoming connection with no remote information:"
                f"socket={repr(socket)}  sockname={sockname}"
            )

        ip, socket, *_ = peername
        remote_address = Address(ip, socket)
        self.logger.debug("Receiving handshake from %s", remote_address)

        try:
            ephem_pubkey, initiator_nonce, initiator_pubkey = decode_authentication(
                msg, self.privkey)
        except DecryptionError as non_eip8_err:
            # Try to decode as EIP8
            got_eip8 = True
            msg_size = big_endian_to_int(msg[:2])
            remaining_bytes = msg_size - ENCRYPTED_AUTH_MSG_LEN + 2
            msg += await self.wait(
                reader.read(remaining_bytes),
                timeout=REPLY_TIMEOUT)
            try:
                ephem_pubkey, initiator_nonce, initiator_pubkey = decode_authentication(
                    msg, self.privkey)
            except DecryptionError as eip8_err:
                raise HandshakeFailure(
                    f"Failed to decrypt both EIP8 handshake: {eip8_err}  and "
                    f"non-EIP8 handshake: {non_eip8_err}"
                )
        else:
            got_eip8 = False

        initiator_remote = Node(initiator_pubkey, remote_address)
        responder = HandshakeResponder(initiator_remote, self.privkey, got_eip8, self.cancel_token)

        responder_nonce = secrets.token_bytes(HASH_LEN)
        auth_ack_msg = responder.create_auth_ack_message(responder_nonce)
        auth_ack_ciphertext = responder.encrypt_auth_ack_message(auth_ack_msg)

        # Use the `writer` to send the reply to the remote
        writer.write(auth_ack_ciphertext)
        await self.wait(writer.drain())

        # Call `HandshakeResponder.derive_shared_secrets()` and use return values to create `Peer`
        aes_secret, mac_secret, egress_mac, ingress_mac = responder.derive_secrets(
            initiator_nonce=initiator_nonce,
            responder_nonce=responder_nonce,
            remote_ephemeral_pubkey=ephem_pubkey,
            auth_init_ciphertext=msg,
            auth_ack_ciphertext=auth_ack_ciphertext
        )

        transport = Transport(
            remote=initiator_remote,
            private_key=self.privkey,
            reader=reader,
            writer=writer,
            aes_secret=aes_secret,
            mac_secret=mac_secret,
            egress_mac=egress_mac,
            ingress_mac=ingress_mac,
        )

        # Create and register peer in peer_pool
        peer = self.peer_pool.get_peer_factory().create_peer(
            transport=transport,
            inbound=True,
        )

        if self.peer_pool.is_full:
            await peer.disconnect(DisconnectReason.too_many_peers)
            return
        elif not self.peer_pool.is_valid_connection_candidate(peer.remote):
            await peer.disconnect(DisconnectReason.useless_peer)
            return

        total_peers = len(self.peer_pool)
        inbound_peer_count = len([
            peer
            for peer
            in self.peer_pool.connected_nodes.values()
            if peer.inbound
        ])
        if total_peers > 1 and inbound_peer_count / total_peers > DIAL_IN_OUT_RATIO:
            # make sure to have at least 1/4 outbound connections
            await peer.disconnect(DisconnectReason.too_many_peers)
        else:
            # We use self.wait() here as a workaround for
            # https://github.com/ethereum/py-evm/issues/670.
            await self.wait(self.do_handshake(peer))